MPA1: Looks very like the Lowe Pro Roller Attaché which gives you 2 bags in one if you need it. Sadly it won't take pro size bodies so no use to me.
I still want someone to make a bag that allows me to carry clothes for a 2 day shoot flying on regional jets as well as my cameras so that I can have only one bag as carry on and breeze through the airport. No bags ever have space for clothes!
Have you tried vacuum-sealing your cloths with plastic vacuum bag (Space Bag) before placing them in the camera bag?